Terminal treatment method and terminal treatment apparatus for coaxial cable

ABSTRACT

A terminal treatment method for a coaxial cable including a core member having an inner conductor covered with an insulator, an outer conductor provided around the core member and formed of a plurality of wires, and a sheath covering an outer circumference of the outer conductor, includes exposing the outer conductor by removing the sheath on an end portion of the outer conductor, and widening a terminal of the outer conductor away from the core member by compressing a terminal-near portion of the exposed outer conductor from an outer circumferential side of the coaxial cable to deform the terminal-near portion of the exposed outer conductor.

CROSS REFERENCE TO RELATED APPLICATION

This application is based on Japanese Patent Applications No.2012-104017 filed on Apr. 27, 2012, the contents of which areincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a terminal treatment method and aterminal treatment apparatus for a coaxial cable having an innerconductor and an outer conductor.

2. Background Art

As electric cables having a shielding function, coaxial cables having anouter conductor covering an outer circumference of an inner conductorhave been used from the past (for example, see JP-A-2004-171952 andJP-A-2007-066825).

Also, a technique for terminal-treating such coaxial cables, in which aninner conductor in a terminal portion thereof is separated from an outerconductor, has been known (for example, see JP-A-H1-081608).

When, for example, an outer conductor is to be separated in a terminalportion of a coaxial cable, or the like, radially outwardly widening anend portion of the exposed outer conductor is performed as apre-treatment.

However, because the outer conductor is wound in a spiral pattern or isattached in a longitudinal direction thereof on an outer circumferenceof a core member having an inner conductor covered with an insulator, itis difficult to easily widen the end portion of the outer conductor.

In addition, there is a case that a coaxial cable, in which an outerconductor disposed on an outer circumference of a core member isintended to be used as a lead like an inner conductor, not as ashielding use, is employed for a wire harness wired in a vehicle, suchas an automobile. For the coaxial cable used as this application,because the outer conductor does not have a small diameter as in theshielding use, it is further difficult to widen the end portion of theouter conductor.

Accordingly, the present invention has been made keeping in mind theabove problems, and an object of the invention is to provide a terminaltreatment method and a terminal treatment apparatus for a coaxial cable,in which an end portion of an outer conductor can be easily widened.

SUMMARY OF THE INVENTION

To achieve the above object, a terminal treatment method for a coaxialcable according to the present invention is characterized by thefollowing (1).

(1) A terminal treatment method for a coaxial cable including a coremember having an inner conductor covered with an insulator, an outerconductor provided around the core member and formed of a plurality ofwires, and a sheath covering an outer circumference of the outerconductor, includes exposing the outer conductor by removing the sheathon an end portion of the outer conductor, and widening a terminal of theouter conductor away from the core member by compressing a terminal-nearportion of the exposed outer conductor from an outer circumferentialside of the coaxial cable to deform the terminal-near portion of theexposed outer conductor.

According to the terminal treatment method for the coaxial cable of (1),the terminal-near portion of the outer conductor is deformed bycompression from the outer circumferential side thereof, so that theterminal portion of the outer conductor can be very easily widened awayfrom the core member. Therefore, enhancement of workability ofsubsequent treatments for the coaxial cable can be achieved.

Also, to achieve the above object, a terminal treatment apparatus for acoaxial cable according to the present invention is characterized by thefollowing (2) or (3).

(2) A terminal treatment apparatus for a coaxial cable including a coremember having an inner conductor covered with an insulator, an outerconductor provided around the core member and formed of a plurality ofwires, and a sheath covering an outer circumference of the outerconductor, includes a terminal widening jig that widens a terminal ofthe outer conductor away from the core member by compressing aterminal-near portion of the exposed outer conductor from an outercircumferential side of the coaxial cable to deform the terminal-nearportion of the exposed outer conductor.

(3) The terminal treatment apparatus for the coaxial cable according tothe above configuration (2) further includes a pair of shaping blocksseparably contacts with each other and has a groove formed on a sidefacing each other. When the shaping blocks become close to each other, aholding hole of a right hexagonal shape or a right octagonal shape isformed by the grooves. When the terminal-near portion of the outerconductor is disposed in the holding hole and then the shaping blocksbecome close to each other, the holding hole is shrunk and theterminal-near portion of the outer conductor is compressed.

According to the terminal treatment apparatus for the coaxial cable of(2), the terminal-near portion of the outer conductor is deformed bycompression from the outer circumferential side thereof by the terminalwidening jig so that the terminal portion of the outer conductor can bewidened away from the core member. Therefore, enhancement of workabilityof subsequent treatments for the coaxial cable can be achieved.

According to the terminal treatment apparatus for the coaxial cable of(3), as the shaping blocks become close to each other, the holding holeof a right hexagonal shape or a right octagonal shape formed by thegrooves is shrunk. Thus, when the terminal-near portion of the outerconductor is disposed in the holding hole, the outer circumference ofthe terminal-near portion of the outer conductor can be substantiallyuniformly compressed so that the end portion of the outer conductor canbe uniformly widened in a concentric circle shape. Therefore,workability of subsequent treatments for the coaxial cable can befurther enhanced.

According to the present invention, a terminal treatment method and aterminal treatment apparatus for a coaxial cable, in which an endportion of an outer conductor can be easily widened, can be provided.

In the foregoing, the present invention has been briefly described.Also, details of the present invention will be further apparent, whenmodes (hereinafter, referred to as “embodiments”) for embodying theinvention as described below are thoroughly read with reference to theaccompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A and 1B are views showing a coaxial cable of which a terminal isto be treated by a terminal treatment method and a terminal treatmentapparatus for a coaxial cable according to the present invention, inwhich FIG. 1A is a perspective view of an end portion thereof and FIG.1B is a sectional view of the end portion.

FIG. 2 is a perspective view of the end portion of the coaxial cable ofwhich the terminal has been treated.

FIG. 3 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor exposing step.

FIG. 4 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor terminal widening step.

FIG. 5 is a front view of a terminal widening jig explaining theterminal widening jig.

FIG. 6 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor terminal widening step.

FIG. 7 is a front view of the terminal widening jig explaining wideningof the outer conductor.

FIGS. 8A and 8B are a side view and a front view of the end portion ofthe coaxial cable of which the terminal portion of the outer conductorhas been widened.

FIG. 9 is a perspective view of the end portion of the coaxial cableexplaining a core mounting step.

FIG. 10 is a perspective view of the end portion of the coaxial cableexplaining a core mounting step.

FIG. 11 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor releasing step.

FIG. 12 is a front view of a chuck jig explaining a state of chuckingthe coaxial cable by the chuck jig.

FIG. 13 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor releasing step.

FIG. 14 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor splitting step.

FIG. 15 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor splitting step.

FIG. 16 is a perspective view of the end portion of the coaxial cableexplaining an inner conductor extracting step.

FIG. 17 is a perspective view of the end portion of the coaxial cableexplaining an inner conductor extracting step.

FIG. 18 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor converging step.

FIG. 19 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor converging step.

FIG. 20 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor intertwining step.

FIG. 21 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor intertwining step.

FIG. 22 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor terminal trimming step.

FIGS. 23A and 23B each are front views showing a terminal widening jigaccording to a reference example 1.

FIGS. 24A and 24B each are front views showing a terminal widening jigaccording to a reference example 2.

DESCRIPTION OF EMBODIMENTS

An exemplary embodiment according to the present invention will be nowdescribed with reference to the accompanying drawings.

In the present embodiment, branching a core member and an outerconductor of a coaxial cable from each other will be described by way ofexample.

FIGS. 1A and 1B are views showing a coaxial cable of which a terminal isto be treated by a terminal treatment method and a terminal treatmentapparatus for a coaxial cable according to the present invention, inwhich FIG. 1A is a perspective view of an end portion thereof and FIG.1B is a sectional view of the end portion, and FIG. 2 is a perspectiveview of the end portion of the coaxial cable of which the terminal hasbeen treated.

As shown in FIGS. 1A and 1B, a coaxial cable 10, of which a terminal isto be treated by the terminal treatment method and the terminaltreatment apparatus according to the present invention, has a structurein which a core member 13 having an inner conductor 11 covered with aninsulator 12 is provided at the center thereof, an outer conductor 14 isprovided around the core member 13 and a sheath 15 also covers an outercircumference of the outer conductor 14.

The inner conductor 11 is, for example, a intertwined wire made of aplurality of copper wires or a single wire made of one copper wire. Theinsulator 12 is formed by an insulation material made of a syntheticresin. The outer conductor 14 is formed by winding a plurality of wires14 a, such as copper wires, in one direction in a spiral pattern. Thesheath 15 is formed by an insulation material made of a synthetic resin.

The coaxial cable 10 is a cable in which the outer conductor 14 isintended to be used as a lead like the inner conductor 11, not as ashielding use, and is used as a wire harness wired in a vehicle, such asan automobile. As this outer conductor 14 of the coaxial cable 10, wiresthicker than wires of a small diameter, such as an outer conductor forshielding, are used.

In the terminal treatment method and the terminal treatment apparatusaccording to the present embodiment, as shown in FIG. 2, the coaxialcable 10 is terminal-treated to become a state in which the sheath 15 onan end portion thereof has been removed and then the core member 13having the inner conductor 11 covered with the insulator 12 have beenbranched from the outer conductor 14. By terminal-treating in this way,the inner conductor 11 can be exposed from an end portion of the coremember 13, and then the inner conductor 11 and the outer conductor 14from which the core member 13 has been branched can be connected to aconnector or the like.

Hereinafter, the terminal treatment method and the terminal treatmentapparatus according to the present embodiment will be described indetail with respect to each of steps thereof.

FIG. 3 is a perspective view of the end portion of the coaxial cableexplaining an outer conductor exposing step, FIG. 4 is a perspectiveview of the end portion of the coaxial cable explaining an outerconductor terminal widening step, FIG. 5 is a front view of a terminalwidening jig explaining the terminal widening jig, FIG. 6 is aperspective view of the end portion of the coaxial cable explaining anouter conductor terminal widening step, FIG. 7 is a front view of theterminal widening jig explaining widening of the outer conductor, FIGS.8A and 8B are a side view and a front view of the end portion of thecoaxial cable of which the terminal portion of the outer conductor hasbeen widened, FIG. 9 is a perspective view of the end portion of thecoaxial cable explaining a core mounting step, FIG. 10 is a perspectiveview of the end portion of the coaxial cable explaining a core mountingstep, FIG. 11 is a perspective view of the end portion of the coaxialcable explaining an outer conductor releasing step, FIG. 12 is a frontview of a chuck jig explaining a state of chucking the coaxial cable bythe chuck jig, FIG. 13 is a perspective view of the end portion of thecoaxial cable explaining an outer conductor releasing step, FIG. 14 is aperspective view of the end portion of the coaxial cable explaining anouter conductor splitting step, FIG. 15 is a perspective view of the endportion of the coaxial cable explaining an outer conductor splittingstep, FIG. 16 is a perspective view of the end portion of the coaxialcable explaining an inner conductor extracting step, FIG. 17 is aperspective view of the end portion of the coaxial cable explaining aninner conductor extracting step, FIG. 18 is a perspective view of theend portion of the coaxial cable explaining an outer conductorconverging step, FIG. 19 is a perspective view of the end portion of thecoaxial cable explaining an outer conductor converging step, FIG. 20 isa perspective view of the end portion of the coaxial cable explaining anouter conductor intertwining step, FIG. 21 is a perspective view of theend portion of the coaxial cable explaining an outer conductorintertwining step, and FIG. 22 is a perspective view of the end portionof the coaxial cable explaining an outer conductor terminal trimmingstep.

(Outer Conductor Exposing Step)

An outer conductor exposing step of exposing the outer conductor 14 isperformed.

Specifically, the sheath 15 on an end portion of the coaxial cable 10 iscut by a cutter or the like. Then, the sheath 15 located more toward theend than the cut location is pulled out in a direction toward the end.As a result, as shown in FIG. 3, the outer conductor 14 is exposed by apredetermined length.

(Outer Conductor Terminal Widening Step)

An outer conductor terminal widening step for widening a terminal of theouter conductor 14 exposed in the outer conductor exposing step isperformed.

In the outer conductor terminal widening step, a gripping jig 21 and aterminal widening jig 71 are used as shown in FIG. 4.

The gripping jig 21 includes a pair of gripping blocks 23 each having agripping recess 22 of a circular arc shape corresponding to an outerdiameter of the sheath 15 formed therein, and grips an end portion ofthe sheath 15 of the coaxial cable 10 by the gripping recesses 22.

As shown in FIG. 5, the terminal widening jig 71 includes shaping blocks72 arranged on the left and right sides of the outer conductor 14 of thecoaxial cable 10. The shaping blocks 72 each have shaping blades 73 onupper and lower sides thereof, and the upper and lower shaping blades 73of the left and right shaping blocks 72 are alternately offset from eachother along the axial direction of the coaxial cable 10. The shapingblocks 72 are each provided with a pressing groove 74 formed on a sidethereof facing the outer conductor 14 by the upper and lower shapingblades 73. Also, the pressing grooves 74 has a straight line portion 74a formed at a bottom part thereof, so that the pressing groove 74becomes a trapezoid shape. Therefore, in a state in which aterminal-near portion of the outer conductor 14 of the coaxial cable 10is disposed between the pressing grooves 74 of the shaping blocks 72,when the shaping blocks 72 become close to each other as shown in FIG.6, a right hexagonal-shaped holding hole A is formed between the shapingblocks 72 as shown in FIG. 7.

In the outer conductor terminal widening step using the gripping jig 21and the terminal widening jig 71 as described above, as show in FIG. 4,the gripping blocks 23 of the gripping jig 21 become close to each otherin a state in which the end portion of the sheath 15 of the coaxialcable 10 is disposed between the gripping blocks 23. As a result, theend portion of the sheath 15 of the coaxial cable 10 is gripped by thegripping recesses 22 of the gripping blocks 23

In this way, in a state in which the end portion of the sheath 15 of thecoaxial cable 10 is gripped by the gripping jig 21, as shown in FIG. 6,the shaping blocks 72 are moved toward the outer conductor 14 at alocation of approximately 1 mm to 10 mm from the terminal of the outerconductor 14. Then, as shown in FIG. 7, the shaping blocks 72 providedon the left and right sides are intersected such that the shaping blades73 are engaged with each other, while holding the terminal-near portionof the outer conductor 14 in the pressing grooves 74. Therefore, theshaping blades 73 of the shaping blocks 72 and the straight lineportions 74 a of the pressing grooves 74 are pressed against the outerconductor 14 held in the pressing grooves 74 from the outercircumference thereof. As a result, the outer conductor 14 around thecore member 13 is compressed and bent toward the center thereof at alocation pressed by the shaping blades 73 and the straight line portions74 a of the pressing grooves 74.

When the outer conductor 14 is compressed toward the center thereof theshaping blades 73 of the shaping blocks 72 and the straight lineportions 74 a of the pressing grooves 74, as shown in FIGS. 8A and 8B,the outer conductor 14 located more toward the terminal than the pressedlocation is widened in an outward radial direction opposite to thepressing direction to be separated from the insulator 12 constitutingthe core member 13.

In this case, each of the shaping blocks 72 includes the pressing groove74 having the straight line portion 74 a at the bottom part thereof, andthus by allowing the shaping blocks 72 to become close to each other,the right hexagonal-shaped holding hole A is formed between the shapingblocks 72. Also, as the shaping blocks 72 become close to each other,opposing portions of the shaping blades 73 and opposing straight lineportions 74 a of the pressing grooves 74 become gradually close to eachother, so that the holding hole A between the shaping blocks 72 isshrunk. As a result, the shaping blades 73 and the straight lineportions 74 a of the pressing grooves 74 are contacted with the outercircumference of the outer conductor 14 compressed by the pressinggroove 74 of each of the shaping blocks 72 without any gap andsubstantially uniformly, so that the outer circumference of the outerconductor 14 is uniformly compressed. Therefore, the outer conductor 14of the coaxial cable 10 is uniformly widened in a concentric circleshape.

If the terminal of the outer conductor 14 is not sufficiently widenedeven when the outer conductor 14 is shaped by the terminal widening jig71 in that way, after the shaping blocks 72 are first separated fromeach other and then are shifted from the compressed location of such afirst time in a direction away from the terminal, the shaping blocks 72are again pressed against the outer conductor 14. Then, the outerconductor 14 is deformed in the outward radial direction at twolocations along the axial direction, thereby further widening theterminal of the outer conductor 14.

(Core Mounting Step)

When the outer conductor 14 has been widened at the terminal thereof bythe outer conductor terminal widening step as shown in FIG. 9, acylindrical core 81 formed of, for example, a hard resin or a metal isinserted and mounted onto the terminal portion of the core member 13 asshown in FIG. 10.

(Outer Conductor Releasing Step)

When the core 81 has been mounted on the core member 13, an outerconductor releasing step for unwinding and separating the exposed outerconductor 14 from the core member 13 is performed.

In the outer conductor releasing step, a chuck jig 31 is used as shownin FIG. 11.

As shown in FIG. 12, the chuck jig 31 includes three chuck bodies 32arranged in equal intervals and the chuck bodies 32 are adapted to movein a radial direction. These chuck bodies 32 each have a pressing recess33 on the center side of the arrangement thereof, and the chuck jig 31is provided, at the center of the arrangement of the chuck bodies 32,with an inserting hole 34 surrounded by the pressing recesses 33. Thechuck jig 31 is adapted such that the chuck bodies 32 can rotate aboutthe inserting hole 34.

In the outer conductor releasing step using and the chuck jig 31, asshown in FIG. 11, after an end portion of the outer conductor 14 of thecoaxial cable 10 has been inserted in the inserting hole 34 of the chuckjig 31, the chuck bodies 32 are moved toward the center of thearrangement thereof. Therefore, the outer conductor 14 is pressed andfixed from an outer circumferential side thereof by the pressing recess33 of each of the chuck bodies 32.

In this state, as shown in FIG. 13, the chuck bodies 32 of the chuck jig31 are rotated in a direction opposite to a winding direction of theouter conductor 14 wound in a spiral pattern. Then, the outer conductor14 is unwound, so that each of wires 14 a is loosened and becomes astate inflated away from the core member 13.

In the outer conductor releasing step, as shown in FIGS. 11 and 12, whenthe outer conductor 14 is pressed from the outer circumferential sidethereof by the pressing recess 33 of each of the chuck bodies 32 of thechuck jig 31, the outer conductor 14 is sandwiched and fixed between anouter circumferential surface of the core 81 and the pressing recesses33 of the chuck bodies 32, thereby eliminating or reducing a pressingload to the core member 13 having the inner conductor 11. Also, in astate in which the outer conductor 14 is fixed by the chuck jig 31, whenthe chuck bodies 32 are rotated to untwist the outer conductor 14, thecore 81 together with the outer conductor 14 is rotated, therebyeliminating or reducing a torsion load to the core member 13 having theinner conductor 11.

A rotation angle θ of the chuck bodies 32 can be calculated from anaxial length dimension L (mm) of the exposed outer conductor 14 and atwisting pitch P (mm/rev) of the outer conductor 14 using the followingequation.

θ=L/P

(Outer Conductor Splitting Step)

An outer conductor splitting step for splitting the outer conductor 14unwound and separated from the core member 13 is performed.

In the outer conductor splitting step, splitting jigs 41 are used asshown in FIG. 14. The splitting jigs 41 are provided on left and rightsides of the end portion of the coaxial cable 10 and are adapted to bemoved relative to the coaxial cable 10 in a direction perpendicular toan axial direction thereof. Each of the splitting jigs 41 includes apair of splitting bodies 43 having a splitting piece 42 protrudingtoward the coaxial cable 10, and the splitting bodies 43 are adapted tobe opened relative to each other in an upward-downward direction.

In the outer conductor splitting step using the splitting jig 41 asdescribed above, as shown in FIG. 14, the splitting jigs 41, of each ofwhich the splitting bodies 43 has been closed relative to each other,become close to the coaxial cable 10, and then the splitting pieces 42are inserted into the unwound and inflated outer conductor 14.

In this state, as shown in FIG. 15, the splitting bodies 43 of each ofthe splitting jigs 41 are opened relative to each other in anupward-downward direction and also the chuck bodies 32 of the chuck jig31 is radially outwardly moved to release fixation of the end portion ofthe outer conductor 14. Then, the outer conductor 14 is split into twoupper and lower groups of wires 14 a, gaps S are formed between thegroups of wires 14 a, and thus the core member 13 is exposed in the gapsS.

(Inner Conductor Extracting Step)

When the outer conductor 14 has been split into two groups of wires 14a, an inner conductor extracting step for extracting the core member 13having the inner conductor 11 is performed.

In the inner conductor extracting step, an extruding jig 51 is used asshown in FIG. 16. The extruding jig 51 is provided on one side of theend portion of the coaxial cable 10 and is adapted to be moved relativeto the coaxial cable 10 in a direction perpendicular to the axialdirection thereof. The extruding jig 51 have a holding groove 52 formedon a corner portion of a distal end thereof, which is away from the endportion of the coaxial cable 10, for holding the core member 13 of thecoaxial cable 10.

In the inner conductor extracting step using the extruding jig 51 asdescribed above, as shown in FIG. 17, the extruding jig 51 becomes closeto the coaxial cable 10 and then is pressed into one gap S formed on theouter conductor 14. Then, the core member 13 is inserted and held in theholding groove 52 of the extruding jig 51 and at the same time, islaterally pressed by the extruding jig 51 to be bent at a portionlocated toward an end portion of the sheath 15. As a result, the coremember 13 having the inner conductor 11 is extruded and extracted out ofthe outer conductor 14 through the other gap S.

(Outer Conductor Converging Step)

When the core member 13 having the inner conductor 11 has beenextracted, an outer conductor converging step for converging the outerconductor 14 is performed.

In the outer conductor converging step, a converging jig 61 is used asshown in FIG. 18. The converging jig 61 includes converging blocks 62arranged in pairs on each of left and right sides of the outer conductor14 of the coaxial cable 10. The converging blocks 62 are alternatelyarranged to be offset in position on the left and right sides of theouter conductor 14 along the axial direction of the coaxial cable 10,and each are adapted to be moved relative to the outer conductor 14 in adirection perpendicular to the axial direction. The converging blocks 62are each provided with a V-groove 64 on a side thereof facing the outerconductor 14.

In the outer conductor converging step using the converging jig 61 asdescribed above, as shown in FIG. 19, the converging blocks 62 are movedtoward the outer conductor 14 in a state in which the core member 13 isoriented upward. Then, the converging blocks 62 provided on the left andright sides are intersected to be overlapped on each other while holdingthe outer conductor 14 in the V-grooves 63. As a result, the outerconductor 14 held in the V-grooves 63 is sandwiched by the convergingblocks 62 and thus is converged on an axis of the coaxial cable 10.

(Outer Conductor Intertwining Step)

An outer conductor intertwining step for intertwining the convergedouter conductor 14 is performed.

In the outer conductor intertwining step, the chuck jig 31 as describedabove is used as shown in FIG. 20. In the outer conductor intertwiningstep using the chuck jig 31, the chuck bodies 32 are moved toward thecenter of the arrangement thereof, in a state in which the end portionof the outer conductor 14 of the coaxial cable 10 is inserted in theinserting hole 34 of the chuck jig 31. As a result, the end portion ofthe outer conductor 14 is pressed and fixed from an outercircumferential side thereof by the pressing recess 33 of each of thechuck bodies 32.

In this state, as shown in FIG. 21, the chuck bodies 32 of the chuck jig31 are rotated in one direction. Then, the wires 14 a of the outerconductor 14 are intertwined.

Preferably, the rotation direction is the same direction as the windingdirection of the outer conductor 14 which has been previously wound in aspiral pattern. Also, the rotation number of the chuck bodies 32 can bevaried depending on material properties of the wires 14 a of the outerconductor 14, but is preferably approximately 2 to 3 revolutions. Inaddition, when the wires 14 a of the outer conductor 14 have beenintertwined, the outer conductor 14 is shrunk in the axial direction dueto intertwining. Therefore, the chuck jig 31 is adapted to be movedalong the axial direction of the coaxial cable 10, and during the outerconductor intertwining step, the chuck jig 31 is moved in the axialdirection corresponding to the outer conductor 14 shrunk due tointertwining.

(Outer Conductor Terminal Trimming step)

As shown in FIG. 22, an outer conductor terminal trimming step, in whichthe terminal portion of the outer conductor 14 fixed by the chuck jig 31and thus having a chuck mark formed thereon is cut and removed by acutter or the like, is performed.

By performing the foregoing steps, the core member 13, which includesthe inner conductor 11, and the outer conductor 14 of the end portion ofthe coaxial cable 10 are branched from each other, and thus each becomea state of capable of connecting to a connector or the like.

In this way, according to the terminal treatment method and the terminaltreatment apparatus for the present embodiment, the terminal-nearportion of the outer conductor 14 is deformed by compression from theouter circumferential side thereof by the terminal widening jig 71 sothat the terminal portion of the outer conductor 14 can be widened awayfrom the core member 13. Therefore, enhancement of workability ofsubsequent treatments for the coaxial cable 10 can be achieved.

For example, by widening the terminal of the outer conductor 14 of thecoaxial cable 10 in a concentric circle shape, workability of the coremounting step for protecting the core member 13 having the innerconductor 11 can be enhanced and also the outer conductor 14 can beevenly untwisted in the outer conductor releasing step, therebyachieving enhancement of quality.

Also, as the shaping blocks 72 become close to each other, the righthexagonal-shaped holding hole A formed by the pressing grooves 74 isshrunk. Thus, when the terminal-near portion of the outer conductor 14is disposed in the holding hole A, the outer circumference of theterminal-near portion of the outer conductor 14 can be substantiallyuniformly compressed so that the end portion of the outer conductor 14can be uniformly widened in a concentric circle shape. Therefore,workability of subsequent treatments for the coaxial cable 10 can befurther enhanced.

In addition, although the foregoing embodiment has been described, byway of example, with respect to a case in which the shaping blocks 72 ofthe terminal widening jig 71 become close to each other, thereby formingthe holding hole A having a right hexagonal shape, the shape of theholding hole A may be a right octagonal shape.

Also, according to the foregoing embodiment, during the outer conductorreleasing step, the outer conductor 14 is rotated in a directionopposite to the winding direction of the outer conductor 14 wound in aspiral pattern to be loosened. However, in a case of a coaxial cable 10having an outer conductor 14 attached in a longitudinal directionthereof, the end portion of the outer conductor 14 is gripped by thechuck jig 31 and then the chuck jig 31 is moved in the axial directionaway from the end portion, thereby loosening the outer conductor 14.

Herein, to illustrate further advantages of the present invention,reference examples of a terminal widening jig will be described.

Reference Example 1

FIGS. 23A and 23B each are front views showing a terminal widening jigaccording to a reference example 1.

As shown in FIG. 23A, the terminal widening jig 91 of the referenceexample 1 includes shaping blocks 92 each provided with a U-groove 94for compressing the outer conductor 14 of the coaxial cable 10.

As shown in FIG. 23B, if the shaping blocks 92 of the terminal wideningjig 91 become close to each other with the outer conductor 14 of thecoaxial cable 10 held in the grooves 94, bottoms of the grooves 94become close to each other to compress the outer conductor 14. However,even when the shaping blocks 92 become further close to each other, apressing force to a portion of the outer conductor 14 located near edgesof the grooves 94 is not increased, and thus compressing forces on upperand lower portions of the outer conductor 14 are insufficient. As aresult, the outer conductor 14 is not uniformly compressed in acircumferential direction thereof, thereby causing a variation inwidening of the terminal of the outer conductor 14.

Reference Example 2

FIGS. 24A and 24B each are front views showing a terminal widening jigaccording to a reference example 2.

As shown in FIG. 24A, the terminal widening jig 95 of the referenceexample 2 includes shaping blocks 96 each provided with a V-groove 98for compressing the outer conductor 14 of the coaxial cable 10.

As shown in FIG. 24B, if the shaping blocks 96 of the terminal wideningjig 95 become close to each other with the outer conductor 14 of thecoaxial cable 10 held in the grooves 98, the grooves 94 compress theouter conductor 14. However, spaces G are created in valley portions ofthe grooves 98 and portions engaged between the grooves 98 of theshaping blocks 96, and thus compressing forces in the spaces G areinsufficient. As a result, the outer conductor 14 is not uniformlycompressed in a circumferential direction thereof, thereby causing avariation in widening of the terminal of the outer conductor 14.

The present invention is not limited to the foregoing embodiment, butappropriate changes, modifications or the like thereof can be made. Inaddition, material, shape, dimension, number, installation location andthe like of each of the components of the foregoing embodiment are notlimited but arbitrary if the present invention can be achieved.

What is claimed is:
 1. A terminal treatment method for a coaxial cableincluding a core member having an inner conductor covered with aninsulator, an outer conductor provided around the core member and formedof a plurality of wires, and a sheath covering an outer circumference ofthe outer conductor, the terminal treatment method comprising: exposingthe outer conductor by removing the sheath on an end portion of theouter conductor; and widening a terminal of the outer conductor awayfrom the core member by compressing a terminal-near portion of theexposed outer conductor from an outer circumferential side of thecoaxial cable to deform the terminal-near portion of the exposed outerconductor.
 2. A terminal treatment apparatus for a coaxial cableincluding a core member having an inner conductor covered with aninsulator, an outer conductor provided around the core member and formedof a plurality of wires, and a sheath covering an outer circumference ofthe outer conductor, the terminal treatment apparatus comprising: aterminal widening jig that widens a terminal of the outer conductor awayfrom the core member by compressing a terminal-near portion of theexposed outer conductor from an outer circumferential side of thecoaxial cable to deform the terminal-near portion of the exposed outerconductor.
 3. The terminal treatment apparatus for the coaxial cableaccording to claim 2 further comprising: a pair of shaping blocks thatseparably contacts with each other and has a groove formed on a sidefacing each other, wherein, when the shaping blocks become close to eachother, a holding hole of a right hexagonal shape or a right octagonalshape is formed by the grooves, and when the terminal-near portion ofthe outer conductor is disposed in the holding hole and then the shapingblocks become close to each other, the holding hole is shrunk and theterminal-near portion of the outer conductor is compressed.